It's not as complex as you make it sound. The parser should pass along any non-terminal characters without issue.

The rest of the edge cases (ex newlines in data) can be handled by using a proper DFM (Deterministic Finite State Machine). None of that String.split('\n').split(',') garbage.

If you're processing text as binary without using a string reader that can differentiate between UTF-8 and ASCII then you're doing it wrong.

With that said, I agree completely that people should use an established library. Code that has been viewed, used, broken by thousands of users is infinitely better than any home grown variant.

Source: With lots of blood sweat and tears I authored one of those 'solid' libraries.